I have this very irritating humming noise coming from the car when driving, it is worse when the car is off the accelerator. It has been looked at and it appears to be the pipe vibrating that runs from the high pressure pump to the engine. When a stethoscope has been placed on the pipe it sounds deafening like a pneumatic drill.

Just wondered if anyone else has had this problem? I'm assuming it's coming from the high pressure pump.